Motion platforms are used in a wide variety of applications. For example, motion platforms may be used in vehicle simulators (e.g., aircraft simulators) for training purposes as well as recreational purposes. As explained in US Patent Publication No. 2006/0222539, a motion platform may be moved about its one or more axes by operation of one or more actuators positioned beneath the motion platform, as illustrated in FIG. 1 of the publication. Also, as explained in the publication, transducers may be employed for determining the position of or the orientation of the motion platform.
Each transducer in US Patent Publication 2006/0222539 is positioned “immediately adjacent to an actuator.” A microprocessor then receives and decodes signals from the transducers and, based thereon, calculates the position or the orientation of the motion platform. The calculations can then be used to feedback control signals to the actuators to further control and/or correct the position or orientation of the motion platform.
Each transducer also may be employed to provide end of travel (EOT) protection for the corresponding actuator. As such, each transducer would more specifically provide discrete position sensing for the corresponding actuator in order to determine the degree to which the actuator is extended or retracted and prevent the actuator from operating outside its intended range.
In high speed applications particularly, the microprocessor must receive the output signals from the transducers and make the aforementioned calculations quickly and accurately. This ability is, at least in part, dependent on the complexity of the calculations. In US Patent Publication 2006/0222539, the calculations may be quite complex because the output signal from each transducer is not continuously proportional to the state of the corresponding actuator and, in addition, the output of each actuator will influence the output signal of both transducers due to cross-coupling effects. The microprocessor must then solve for this lack of proportionality and the cross-coupling effects, which may result in a time consuming and complicated computational process.
As mentioned above, there are a variety of applications for which motion platforms are employed. Vehicle simulators are but one example. Another example is amusement rides, such as dark ride vehicles, which are in use at many amusement and/or theme parks around the world. Examples of dark ride vehicles are described and claimed, for example, in U.S. Pat. No. 7,094,157, entitled AMUSEMENT RIDE VEHICLE WITH PNEUMATICALLY ACTUATED CABIN AND MOTION BASE, the entire contents of which are incorporated by reference herein. Other exemplary dark ride vehicles are described and claimed in pending U.S. patent application Ser. No. 13/470,244, entitled TRACKLESS DARK RIDE VEHICLE, SYSTEM, AND METHOD, the entire contents of which are also incorporated by reference herein.
Accordingly, a motion platform configuration is needed where the aforementioned computations are less complex. This will provide better support particularly for high speed motion platform applications.